PhonemyPC is great, but it's $10. Emailed the dev today actually because I was having problems w/ it... Everytime my computer would sleep and my login screen would come up to log in, the app on my phone would still show my desktop no matter what I did so I would click things and nothing would happen. Other than that, great app.

PhomeMyPC was the easiest for me to get up and running and you have many choices on it's operation:
Control Mouse & Keys (wireless keyboard and Mouse operation).
Stealth Live View
Interact View
Execute Actions (set up one click actions)
Control Processes
Control Windows

The developers are very responsive to feedback. Well worth the $10 bucks.